Automobile race cars have always been one of the
most electrifying things a person could experience — now
they are also electrified, or maybe electronified. Getting a
first-hand look at the preparation of the IndyCar racing machine of
Tony Kanaan and KV Racing at the track in Sonoma recently was quite
the experience and certainly an exploration of technology.
Here’s a review of some of the technical/operational
points of the car and the track-side systems.

Fig 1: Tony Kanaan’s #11
IndyCar.

Fig 2: Number 11 gets ready to enter the
track.

700 horsepower engines

The engines and chassis are new this year in
IndyCar and race officials are tightly controlling what each team
uses in order to control costs and keep a level playing field.
During a full season, each entrant will be provided with no more
than five fresh-built engines. Using more than five in a season
will result in a penalty. An unapproved engine change currently
costs a team 10 spots on the starting grid.

The single- or twin-turbocharged 2.2 L V6
engines have four-valves-per-cylinder, run as high as 12,000 RPM,
and yield 550 to 700 horsepower and about 300 lb-ft of torque. They
are built by three manufacturers — Chevy, Honda, and
Lotus. Interestingly, all engines are tracked by a GPS monitoring
system so officials know just what is going on. An IndyCar gets 1.9
to 2.5 miles per gallon and runs E85 Ethanol fuel.

Engine life is set at 1,850 miles, so they
either go that long or are blown — something that has
happened fairly often this year, with the new design. Almost all
racers were already using their 5th or 6th engine at Sonoma, with
two races yet to go — the Grand Prix of Baltimore on city
streets September 2nd and the Fontana, CA 500 mile oval track race
on September 15th.

Tony Kanaan’s car has a Chevrolet
engine. His best average lap speed during practice sessions was
108.213 mph and he qualified 18th, but started 16th after two
penalties were dished out.

Computers and telemetry

The TAG-400i engine control unit (ECU) is made
by McClaren Electronic Systems of the United Kingdom and
Huntersville, NC in the U.S. The compact unit resides on the left
side of the car near the cockpit and runs on 7.9 to 16.0 Vdc. The
unit has extensive protection against power transients, EMI, and
reverse polarity. It uses the TAGOS 32-bit RTOS with 1 Gbyte of
storage and a 264-MHz Power PC MCU from Freescale.

Fig 3: One of many team laptops is used to
check engine sensor data.

Fig 4: ECU and telemetry unit are on the
car’s left side.

There is a wealth of sensors on the car. Inputs
to the ECU include:

Four inductive speed sensors (two crank sync;
two turbo speed)

One differential hall effect (DHE) cam
sensor

Four DHE speed sensors

Seven NTC temperature sensors

Twenty-three 0 to 5 V analog inputs

Two K-type thermocouples

Two wideband Lambda sensors

Four knock sensors

I/O includes four CAN ports and one Ethernet
port. The software in the McLaren ECUs must adhere to the
turbocharger boost requirements, which change from race to race.
The software cannot be changed by race crews — only
McLaren modifies the software so that all teams use the same
profile.

Fig 6: The two telemetry antennas reside
on left side above the fuel filler port.

Cosworth supplies real-time wireless telemetry
of the data between the car and the pits as well as the data
collection and analysis software the teams use for analysis. The
Cosworth system provides data for the real-time TV coverage as
well. The fin antenna shown in the photo are used for TV coverage.
The antennas above the gas filler on the cars left side are for
sensor telemetry, which has 200 channels.

At track side, members of the pit crew are
constantly analyzing data on six or seven computer screens and the
driver can see selected data fed back to his/her steering wheel.
The trackside team cannot adjust anything on the car —
only monitor things. And they monitor a lot, as noted with the
sensor list above.

Fig 7: The pit crew analyzes race
data.

Fig 8: KV Racing’s James
Sullivan briefs Speed2Design winners.

One thing they watch carefully is the fuel map
— how much fuel is being used and what that means for the
pit-stop strategy. There is a track map with speed history for
every corner and the software can estimate the speed and fuel usage
for the next lap.

Real-time adjustments

The driver can adjust suspension during the race
in two ways. One is a tool called the weight jacker. This is a
hydraulic cylinder that affects the stiffness of the springs to
change the effective weight distribution of the car. There are two
weight jackers: one that controls the distribution from front to
back, and one for right to left. The driver adjusts this at almost
every corner and the track team can see the results on sensors and
also note the speed through that corner. The driver can also adjust
the cars roll-bar stiffness. The driver, of course, has continuous
voice contact with the pit.

Fig 9: The cars steering wheel is also its
information center.

Fig 10: The steering wheel used by Tony
Kanaan.

The driver is also monitored for EKG and G
force. Operating the car involves forces on the head of up to 4.5
lateral Gs while cornering — left, right, and then left
again — it is a constant beating, despite ample padding
on both sides of the protective helmet surround piece in the
cockpit.

Transmission, down force, and fuel

IndyCar uses a new six speed P1011 transmission
from Xtrac, made especially for the new Dallara chassis. It
features an easily removable gear cluster from the rear of the
gearbox. The unit’s configuration can be easily changed
between ovals and road course specifications and it features an
easily adjustable differential and an integrated assisted
gear-change system (AGS).

Fig 11: Adjusting the transmission in the
garage.

Fig 12: The P1011 transmission gear
cluster.

The cars weigh just 1500 pounds and it relies on
front and rear wings to provide down force to hold it on the track.
The front wing is adjustable in the pits and, on an oval track
especially, the left and right side are set differently. The cars
fuel tank holds 18.5 gallons and that entire amount can be put in
during a pit stop in just 2.5 seconds.

Speed2Design

Littlefuse invited me to the race as part of
their Speed2Design promotion. The program highlights the unique
challenges EE’s are facing today and provides the tools
need to address these challenges in the area of circuit protection
and safety.

The Littelfuse’s website serves as a
“rapid-response center” for time-pressured
electronic engineers seeking answers and information about proper
circuit protection technology, selection, and best practices in
design. It features tutorials, selector guides, design kits,
webcasts, sample circuits, and a Q&A forum.

Littlefuse’s Speed2Design contest
brigs five EE’s to each IndyCar race this year. The five
at this Sonoma race were: Tom from Medtronic in Boston, Charles
from BAE Systems in northern Virginia, Brian from Combi Packaging
Systems in Canton, Ohio, Adam from Alion Science and Technology in
California, and Morgan from Marshall Medical Center in Placerville,
CA. Great guys and they had a grand time with a
close-up-and-personal look at IndyCar. The Speed2Design portal
(www.speed2design.com) has more race and car technology
information.

Gordon Hunter, Littelfuse President and CEO, was
at the track Sunday morning and talked with Speed2Design winners
and the #11 race team.

Ryan Briscoe won the race on a beautiful 75
degree Sunday afternoon, with teammate Will Power second, just
about a half-second behind. Dario Franchitti was third and Rubens
Barrichello fourth. Tony came in 10th, even after damaging his
front wing in the very first lap and a problem during his final pit
stop on lap 63 when, for a while, car refused to go into first gear
because of a software problem that affected the clutch.
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